Stoker



T. JENNINGS.

STOKER.

APPLICATION FILED FEB. 18. I918.

Patented Sept. 20, 1921.

3 SHEETSSHEET I.

T.JENNING&

STOKER.

APPLICATION FILED FEB. I8. 1918.

Patented Sept. 20, 1921.

3 SHEETSSHEE'[ 2.

InverIW T. JENNINGS.

Patented Sept. 20, 1921 3 SHEETS-SHEET 3.

I I I -J IIHW m R Que he w w. I. H I I ,1 e I I I II I UNITED" STATES Parana .oFFicE.

THOMAS JENNINGS, OF CINCINNATI, OHIO, ASSIGNOR TO THE UNDERFEED STOKER COMPANY OF AMERICA, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

STOKER.

Specification of Letters Patent.

Patented Sept. 20, 1921.

To all whom it may concern:

Be it known that I, THOMAS JENNINGS, a subject of the King of Great Britain, residing in the city of Cincinnati, county of Hamilton, and State of Ohio, have invented certain new and useful Improvements in Stokers, of which the following is a specification.

My invention has for its general object to provide an improved and efficient underfeed furnace that is self-cleaning and is particularly adapted for small installations.

Explanatorily I may point out that large furnaces are usually installed in furnace rooms especially designed to receive them, built with such floor levels, ash pits, chutes and other special arrangements as accommodate rearwardly inclined or traveling grates or other known appliances for delivering ash from the fire-box (i. 6. selfcleaning). There is, however, a great demand for smaller furnaces, which, as ,to setting, require no variation from ordinary flat-floored basement construction but which will, nevertheless, combine high heating eflicienc with labor-saving ease of operation and sel -cleaning. It is to the satisfaction of this demand that my present invention is especially directed, although it will be understood that Izome of its features may have wide applicaility. 4

In the embodiment of my invention I provide, in general, a furnace having a fire-box with its floor, flanking the retort or retorts,

disposed approximately horizontally foreand-aft, but preferably sloping downwardly from the center toward its sides; I preferably arrange the air supply twyers in special fashion to insure the fullest combustionin a middle longitudinal zone; and provide advantageous means for effecting a lateral feed of the ash away from such zone toward closable ash-dump openings properly arranged along the side zones of the fire box. Special features of my invention and further objects and advantages thereof will become apparent from the following description, taken in conjunction withthe accompanying drawings, wherein I have illustratively shown a single embodiment of the invention and in which Figure 1 is an end view of the principal parts hereinafter described viewed from just inside the front wall of the furnace and with portions broken away;

Fig. 2'is a side view broken away of several lines as indicated by the broken line 2-2 of Fig. 3;

Fig. 3 is a plan view of the fire-box floor construction Figs. 1 and 5 are details of detached elements of the self-cleaning structure; Figs. 6 and 7 are details of twyer blocks, Fig. 8 is a frame-element detail.

I have shown in the drawings a single retort furnace set on a flat support, to indicate non-special setting and small size, but in neither of these particulars is my invention necessarily limited to the conditions assumed.

Between the side walls 10 and the end walls 11 of the furnace there spans the floor 12 of the fire-box 13 separating the latter effectively from the central wind-box or air supply chamber 14 and the ash pits 15, except where twyers are provided for supplying air to support combustion. This floor 12 includes the longitudinal troughshaped retort (or-retorts) 16, having a substantially horizontal mouth and its bottom preferably up-sloped toward the rear of the furnace, to which retort green fuel is suppliedfrom the hopper 17 and into and along which such fuel is force-fed as by means of a ram 18 and (preferably) a pusher 19. Such ram may be operated by any suitable reciprocating devices, and as herein illustrated a simple crank and connecting rod mechanism 20 operated through worm gearing 21 controlled from a power-driven vertical shaft 22 constitutes a simple operating mechanism. The ram-operation and the consequent raising and spilling laterally of the live fuel are too well understood to re=- quire extended comment. Suflice it to say that the wind-box 14 below the combustion zone is supplied with air under pressure which is admitted to the combustion space through proper twyers 23 opening to the retort above the green coal level; and further as a preferred feature of my present invention, these twyers are preferably supplemented by others, shown at 24, out-facing or directed toward the side-walls, and'disposed at or near the bottom of the live fuel bed laterally beyond the mouth of the retort. Such arrangement, or equivalent structure for giving a draft through the partly consumed fuel that spills laterally from and lies close to the mouth of h retort, insures .ash is to be delivered toward the furnacesides and dumped into the ash pits 15 for final removal. For these purposes I provide,

close to the side-Walls, means to open a -more or less, and moving and dumping'its i and at the outer edges brackets 35 in which the open-bottomed dump-space through which the ash may fall, and intermediate such side-dumping-zones I arrange means to effect 'a'positive lateral delivery of the ash to the dumping zones. Such devices may be varied in detail, but I so construct that the side-delivery devices which are located over the wind-box, do not, in" operation, substantially open the floor, but effectively prevent air passage, while the dump-gates overthe ash pits normally close the receptive openings, both of such devices forming part of the floor.

Specifically I provide tiltable sections 30 each comprising a plate or plates 31 pivoted as at 32 on a longitudinal axis along its outer edge so that when its inner edge is raised it will force its ash-load up and away from the combustion zone, loosening the adjacentfuel somewhat, breaking up clinkers load toward the adjacent side-wal aterally beyond these sections are dump gates I or wings 33, normally closing dump spaces 34 opening to the ash pits 15, each such wing being movable, of course, to open a passage for ash-deposit. By such arrangements the ash, laterally spilled from the combustion zone and gathering on sections 30, is pushed and spilled by these sections, when lifted, toward and onto the gates-33 which, when dropped, dump the ash into the pits.

n specific construction shown I prefer to mount the retort suitabl .on the end walls of the retort provide tw er-blocks 23' are mounted and held by a 1'0 36 engaging end-ears thereof. Each, such bracket 35 receives the edge of a: frame 38 "that along its inner border carries the supplemental twyer-blocks 24' also rod-' secured in place. The tops of.these rows of blocks are preferably down-sloped toward the side-walls and rovided with shoulders as needed in order that the twyers may open through nearly perpendicular walls to minimize clogging. Each frame has its outer edge supported by a long bracket 40 and forms, with its attached parts, a dead-plate down-sloping somewhat toward its sides and intended, under operating conditions, to substantially exclude the passage of air to the fire-box above. Each of the two tilting sections 30 preferably comprises a number of plates 31 arranged in rib-separated openings 41'inthe frame, such plates being all mounted on a rock-shaft 43 and each plate having ash to spill to the sides as is operable by lever 53.

The brackets 40 and their supporting bases 40' serve as closed partitions to separate the central wind-box from the ash plts, which have doors 54 opening thereto at any desired point. 4

Of course the general side-slope of the fire-box structure gives a tendency of the the fire is underfed, but the positive side-feeding, loosening the fire, breaking clinkers and pushing the ash laterally, all without substantially admitting air, and all effected by tilting of sections 30, makes the arrangement described one very desirable as a specific embodiment of my invention and especially so in conjunction With the, supplemental twyer arrangement and the simple dumping devices at the sides. It will be noted, of course, that the dump-gates 33 are primarily normal closers. for the dump-spaces to complete the dead-plate floor-structure, but advantage resides in the specific construction in that the dump-gate when dropped, like section 30 when raised, dams back the ash (or ash and fuel in thecase of section 30) to a certain extent, preventing avalanching of the ash from sweeping the iron entirely clear. This insures the maintenance of at least a skin of ash on the dead plate to aid in efiecting the desired substantial airseal and also to minimize the chance of burning out or Warping the dead-plate structure.

at I claim is 1. In an underfeed furnace, the combination with a retort having a substantially horizontal mouth, force-feed means for supplying fuel to the retort, and a side-dump closure, at a lower level than the retortmouth, of a floor structure downsloping from the retort-mouth to the side-dump closure and including a fixed plate-receptive openings, plates in said openings pivoted near their outer edges adjacent the floor-level and tiltable to elevate their inner edges to load-avalanching position, said plates having skirts along. their inner edges to dam the openings as the inner edges of the plates are raised and means for pivotally moving said plates to load-avalanching angle.

2. In an underfeed furnace, the combination with a retort having a substantially floor structure having horizontal mouth, force-feed means for supplying fuel to the retort, and a side-dump closure at a lower level than the retortmouth, of a floor structure down-sloping from the retort-mouth to the side-dump closure and including a fixed floor structure having plate-receptive openings, plates in said openings pivoted near their outer edges adjacent the floor-level and tiltable to elevate their inner edges to load-avalanching position, these plates having a common pivotal axis substantially paralleling the side of the retort, and means for pivotally moving said plates to loadeavalanching angle.

3. In an underfeed furnace, the combination with a retort having a substantially horizontal mouth, force-feed means for supplying fuel to the retort, and a side-dump closure at alower level than the retortmouth, of a floor structure down-sloping from the retort-mouth to the side-dump closure and including a fixed floor structure having plate-receptive openings in a row that extends longitudinally substantially parallel to the retort, said row of openings being laterally spaced from the edge of the retort, plates in said openings ivoted near their outer edges adjacent the oor-level and tiltable to elevate their inner edges to load-avalanching position, means for pivotally moving said plates to load-avalanching angle and a wind-chamber below said floor structure, there being twyers opening thrr 'gh the floor structure toward the retort and adjacent the latter, and other twyers opening through the floor structure between the retort margins and said plate-receiving apertures.

4. In an underfeed furnace, side walls, partitions between the side walls flanking a central wind-chamber, a retort between said partitions having a substantially horizontal mouth and means to support a series of downwardly opening marginal twyer blocks, floorstructure frames supported along their inner margins from said retort and down-sloping to and at their outer margins supported on the said partitions, each said frame having therein a row of apertures, plates in said apertures pivoted near their outer edges adjacent the'floor level and tiltable to elevate their inner edges to load-avalanching position, and means for pivotally moving said plates to load-avalanching angle.

THOMAS JENNINGS. 

